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b. 156

composition: Op. 39, Scherzo in C♯ minor

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GC has the entire chord written in minims without dots. The error was corrected in GE.

category imprint: Source & stylistic information

issues: GE revisions , Errors of GC

b. 156-158

composition: Op. 38, Ballade in F major

Slur beyond bar 158 in A

Slur to bar 158 in GC (→GE) & EE

Slur to bar 156 in FE

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The slur in the R.H. in FE ends in bar 156. It is undoubtedly the editor's revision, as bar 156 opens a new line in FE, while in A it is in the middle of the stave, therefore, an accidental break of the started slur is out of the question.

category imprint: Differences between sources

issues: FE revisions

b. 156

composition: Op. 35, Sonata in B♭ minor, Mvt I

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At the beginning of the 2nd half of the bar before the bottom note of the second, GC and FE1 (→FE2) have one  before each of the notes instead of . This easy to detect mistake – none of these flats is necessary at this pitch, whereas a1 appears in the part of the L.H. – was corrected in GE, by adding another  before the bottom note. The correct notation is included in FE3 (→FE4) and EE, which in both cases could have been a result of Chopin's intervention.
A double flat before the top note of the penultimate chord was added only in GE and EE2.

category imprint: Interpretations within context; Differences between sources; Corrections & alterations

issues: EE revisions , Errors in FE , Accidentals in different octaves , GE revisions , Authentic corrections of FE , Errors of GC , Authentic corrections of EE

b. 156

composition: Op. 35, Sonata in B♭ minor, Mvt I

2 slurs in GC & GE2

1 slur in FE (→EE)

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The shortcomings in the slurring of this bar are certainly errors.

category imprint: Differences between sources

issues: Errors in FE , Errors in GE , GE revisions

b. 156-158

composition: Op. 21, Concerto in F minor, Mvt I

1 slur in A

2 slurs in GE1

1 slur in FE (→EE)

2 slurs in GE2

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In the main text, we give the slurs in the L.H. in bars 156 and 158 after A. The half-bar slurs of GE1 (spanning 4 and 3 quavers) are a characteristic arbitrary decision of this edition. In the proofreading of FE (→EE), Chopin combined the slurs within the bars, leaving – as probably less striking – an inaccurately marked starting point of the slurs. GE2 corrected the starting point after A, but not the divisions. 

category imprint: Differences between sources

issues: Errors in GE , GE revisions , Authentic corrections of FE